Artificial tooth



(No Model.)

J. M. TWILLEY.

ARTIFICIAL TOOTH. No. 493,318. Patented Mar. 14, 1893.

UNITED STATES PATENT OFFICE.

JOSHUA M. TWILLEY, OF DOVER, DELAWARE.

ARTIFICIAL T'OOTH.

SPECIFICATION forming part of Letters Patent No. 493,318, dated March 14, 1893. Application filed January 12, 1893. Serial No. 458,116. (No model.)

To all whom, it may concern.-

Be it known that I, JOSHUA M. TWILLEY, a citizen of the United States, residing at Dover, in the county of Kent, State of Delaware, have invented certain new and useful Improvements in Artificial Teeth, of which the following is a specification, reference being had therein to the accompanying drawlugs.

My invention relates to improvements in the form and shape of artificial teeth, and has also reference to the manner of attaching and holding them to a plastic base or gum; and the objects of my invention are to provide artificial teeth in which thestrength after their attachment to the plastic base or gum is not materially impaired by means of the slots, and to provide said teeth with projecting dovetails on the lingual surface of said teeth for attaching and holding them to the plastic base of gum, and which, when so attached will remain firmly attached to the plastic base. I attain these objects by the construction illustrated in the accompanying drawings, in which Figure 1 represents upon an enlarged scale a side View of a front or incisor tooth constructed in accordance with my invention. Fig. 2 is a view of the inner or lingual side of the same tooth. Fig. 3 horizontal section on line x on of Fig. 1 of the same tooth inserted in a plastic base.

In said drawings A represents the bod y of a tooth having its inner or lingual side adapted to be embedded and firmly retained in a plastic gum or base B. The tooth is provided as usual on said side with metal fastenings or pins a the heads of which are adapted to become well anchored in a plastic base provided with a shelf a to form an abutting bearing against the base and relieve the fastenings a from strain but to protect the tooth against lateral displacement and provide a dovetail projecting into the base or gum B, the tooth is provided in its lingual side with nearly vertical grooves a that converge together at their upper ends. Said grooves extend the whole length of the portion of the tooth that is to be embedded and give to the ends of the shelf a a prominent dovetail form to anchor the tooth in the base or gum B, the ends of said shelf being wider at their outer edge than at their inner portion.

I am aware that indentations have been made in the side of the teeth to receive therein a small portion of the base, but the location of said indentation does not prevent the re ception of a suflieient amount of the base to materially strengthen the fastenings, this difficulty is obviated by the location of the grooves a in their lingual surface.

I am also aware that teeth have been provided with metal backing inserted in part in grooves of teeth. I do not use any metal backing but a pre-eminent dovetail on the ends of the shelf a in connection with the vertical grooves.

Having now fully described my invention, I claim An artificial tooth having on the lingual surface thereof a shelf a longer at its outer edge than at its inner portion, with grooves a at the ends of said shelf and in said sur face of the tooth substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

JOSHUA M. TWILLEY.

Witnesses:

E. E. MAssoN, A. B. DEGGES. 

